Die component for a press device

ABSTRACT

A press device includes a base assembly having a base die component configured to form a workpiece and a punch assembly movable relative to the base assembly during a pressing operation. The punch assembly has at least one punch die component pressing the workpiece to form the workpiece. The punch die component includes a main body having a workpiece engagement surface configured to engage the workpiece formed by the base assembly and the punch assembly. The punch die component having a vibration generator operatively coupled to the main body. The vibration generator causes the main body of the die component to vibrate at a high frequency during the pressing operation.

BACKGROUND OF THE INVENTION

The subject matter herein relates generally to die components for pressdevices.

A press device typically includes a base assembly that holds a workpieceand a punch assembly movable by a press ram toward the workpiece andbase assembly to form the workpiece therebetween. The press device isconfigured for high speed stamping having many cycles per second. Theworkpiece, which is positioned between the base assembly and punchassembly, is formed during the pressing operation. A stripper plate istypically positioned between the base assembly and the punch assembly topin the workpiece against the base assembly as the punch assembly isretracted.

Die components are typically held by the punch assembly and/or baseassembly to form the workpiece. The die components have a predeterminedprofile that is used to by punch, stamp, shear, cut, bend or otherwisemanipulate the shape and/or profile of the workpiece. Conventional diecomponents have problems associated with pressing characteristics of thedie components and the workpiece. For example, the die components tendto cause burrs on the edges of the workpiece during blanking as the diecomponents punch through the workpiece. The forces exerted on the diecomponents during repetitive pressing causes wear and damage to the diecomponents, which may also lead to further edge quality problems.

A need remains for a press device having improved pressingcharacteristics.

BRIEF DESCRIPTION OF THE INVENTION

In one embodiment, a press device is provided including a base assemblyhaving a base die component configured to form a workpiece and a punchassembly movable relative to the base assembly during a pressingoperation. The punch assembly has at least one punch die componentpressing the workpiece to form the workpiece. The punch die componentincludes a main body having a workpiece engagement surface configured toengage the workpiece formed by the base assembly and the punch assembly.The punch die component having a vibration generator operatively coupledto the main body. The vibration generator causes the main body of thedie component to vibrate at a high frequency during the pressingoperation.

Optionally, the vibration generator may include a piezoelectricactuator. The vibration generator may include an electrical element anda piezoelectric element configured to change shape when voltage isapplied to the electrical element. The vibration generator may causeultrasonic vibration of the main body.

Optionally, the press device may include a spacer coupled to the mainbody with the vibration generator sandwiched between the spacer and themain body. The press device may include a preload bolt coupled betweenthe spacer and the main body. The preload bolt may connect the spacer tothe main body. The preload bolt may compress the vibration generatorbetween the spacer and the main body. Vibration of the vibrationgenerator may be transmitted into the main body. The spacer may be fixedrelative to the punch assembly. Vibration of the vibration generator maycause the main body to move relative to the spacer.

Optionally, the workpiece engagement surface may be configured tovibrate against the workpiece during the pressing operation. The punchassembly may be moved along a press stroke and a return stroke duringthe pressing operation. The vibration generator may cause the main bodyto vibrate against the workpiece multiple times during the press stroke.The workpiece engagement surface may directly engage the workpiece.Optionally, the main body may include a removable punch. The removablepunch may define the workpiece engagement surface. The removable punchmay be configured to directly engage the workpiece.

In another embodiment, a punch die component for a press device isprovided that includes a main body extending between a first end and asecond end with a workpiece engagement surface at the second endconfigured to engage a workpiece formed by the press device. A vibrationgenerator is coupled to the first end of the main body. The vibrationgenerator operates to cause the main body to vibrate at a high frequencyduring a pressing operation of the press device. A spacer is coupled tothe main body at a spaced apart position. The vibration generator issandwiched between the spacer and the first end of the main body.

In another embodiment, a method of operating a press device is provided.The method includes positioning a workpiece between a base assembly anda punch assembly of the press device, holding a punch die component atthe punch assembly, pressing the punch die component into the workpieceto form the workpiece during a pressing operation of the press device,and vibrating the punch die component against the workpiece at a highfrequency during the pressing operation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a press device formed in accordance with an exemplaryembodiment.

FIG. 2 is a perspective view of a die component for the press device andformed in accordance with an exemplary embodiment.

FIG. 3 is a cross sectional view of the die component.

FIG. 4 is a cross sectional view of a die component for the press deviceand formed in accordance with an exemplary embodiment.

FIG. 5 is a flow chart illustrating an exemplary method of operating apress device.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 illustrates a press device 100 formed in accordance with anexemplary embodiment. The press device 100 is used to form a workpiece102 from a metal sheet, such as by punching, stamping, bending orotherwise manipulating the shape and/or profile of the workpiece 102.The press device 100 may be used to form any type of component from theworkpiece 102, such as terminals or contacts. The press device 100 mayinclude a feed mechanism 104 used to feed the workpiece 102 to a workzone 106. The press device 100 may include a frame or press bed 108 thatsupports other components of the press device 100. The press device 100may be a progressive die machine.

A base assembly 110 is supported on the press bed 108. The base assembly110 supports the workpiece 102 from below during the pressing operation.The press device 100 includes a punch assembly 112 above the baseassembly 110. The punch assembly 112 is driven by a press ram 114 duringa pressing operation toward and/or away from the base assembly 110 topress the workpiece 102 to form the component. Optionally, the punchassembly 112 may be spring biased away from the base assembly 110.Alternatively, the punch assembly 112 may be pulled away from the baseassembly by the press ram 114. In an exemplary embodiment, the punchassembly 112 includes punch die components, generally shown at 116, thatare used to form the workpiece 102. The die components 116 may be thecomponents that engage the workpiece and form the workpiece. Optionally,the base assembly 110 may include one or more base die components, whichmay be similar to the punch die components 116.

In an exemplary embodiment, the base assembly 110 includes a base shoe120 supported by the press bed 108 and a base block 122 mounted to thebase shoe 120. Optionally, the base block 122 may have a predefinedprofile for forming a certain type of component from the workpiece 102.The base block 122 may be replaced by a different base block having adifferent profile to change the type of component manufactured by thepress device 100. Alternatively, the base block 122 may hold one or moreremovable die components that engage and form the workpiece. The baseassembly 110 may include any number of base blocks 122 and/or diecomponents.

In an exemplary embodiment, the punch assembly 112 includes a punch shoe124 and a punch block 126 coupled to the punch shoe 124. The punch block126 and/or the punch shoe 124 may be cam driven, spring driven ormovable by other means relative to the base assembly 110 during thepressing operation. The press ram 114 is used to force the bunch block126 and/or punch shoe 124 toward the base assembly 110 during thepressing operation. The punch block 126 may have a predefined profile toform a certain type of component from the workpiece 102. The punch block126 may be replaced by a different punch block having a differentprofile to form a different type of component from the workpiece 102. Inan exemplary embodiment, the punch block 126 holds one or more of thedie components 116 that directly engage the workpiece to form theworkpiece.

In an exemplary embodiment, the base assembly 110 includes a stripperplate 130 between the base block 122 and the punch block 126. Theworkpiece 102 is feed between the stripper plate 130 and the base block122. The stripper plate 130 pins the workpiece 102 in position duringthe pressing operation. The stripper plate 130 is positioned to engagethe workpiece 102 during withdrawal of the punch block 126 to preventdistortion of the component and/or workpiece 102 and/or to release theworkpiece 102 from the punch block 126. The stripper plate 130 pins theworkpiece 102 against the base block 122 to strip the workpiece 102 fromthe punch assembly 112. Optionally, the stripper plate 130 may be usedto locate the die components 116 during the pressing operation. Forexample, the die components 116 may pass through the stripper plate 130and the stripper plate 130 may hold the side-to-side position of the diecomponents 116 relative to the workpiece 102. Optionally, the diecomponents 116 may be hold by the stripper plate 130 rather than thepunch block 126.

During operation, the workpiece 102 is formed between the base block 122and the punch block 126. The punch shoe 124 is engaged by the press ram114 and is driven toward the base assembly 110 during the pressingoperation of the press device 100. The die components 116 are pressedinto the workpiece as the punch shoe 124 and punch block 126 are forceddownward. The press assembly 112 may be subjected to many pressingcycles per second. In an exemplary embodiment, the punch die components116 may vibrate as the die components 116 are pressed against theworkpiece 102, which enhances the pressing operation and forming of theworkpiece 102. For example, the die components 116 may be vibrated athigh frequency to enhance the pressing operation and forming of theworkpiece 102. The die components 116 may be vibrated many times duringeach press stroke of the pressing operation. The die components 116 maybe vibrated at ultrasonic frequencies. The vibration of the diecomponents 116 may make shearing or cutting through the workpiece 102easier. The vibration of the die components 116 may reduce burrs on theedges of the workpiece 102. The vibration of the die components 116 mayenhance the edge quality of the edges of the workpiece 102. Thevibration of the die components 116 may induce less stress on the diecomponents 116. The vibration of the die components 116 may reduce wearon the die components 116. The vibration of the die components 116 mayallow blanking of thinner material as the die clearances do not need tobe maintained at such precise locations when the die components 116 arevibrated during the pressing operation.

FIG. 2 is a perspective view of the punch die component 116 formed inaccordance with an exemplary embodiment. FIG. 3 is a cross sectionalview of the punch die component 116. The die component 116 includes amain body 140 extending between a first end 142 and a second end 144.The main body 140 has a workpiece engagement surface 146 at the secondend 144 that is configured to engage the workpiece 102 (shown in FIG.1).

The die component 116 includes a vibration generator 150 coupled to thefirst end 142 of the main body 140. The vibration generator 150 isoperated to cause the main body 140 to vibrate at a high frequencyduring a pressing operation of the press device 100 (shown in FIG. 1).In an exemplary embodiment, the vibration generator 150 causes the mainbody 140 to vibrate at ultrasonic frequencies. For example, thevibration generator 150 may cause the main body 140 to vibrate atbetween 20 and 60 kHz. The vibration generator 150 may be operated tocause the main body 140 to operate at different frequencies outside ofultrasonic frequencies in alternative embodiments.

In an exemplary embodiment, the vibration generator 150 includes apiezoelectric actuator 152. The piezoelectric actuator 152 changes shapewhen a voltage is applied to the piezoelectric actuator 152. Forexample, the piezoelectric actuator 152 may expand and contact at highfrequency to cause ultrasonic vibration.

The die component 116 includes a spacer 160 coupled to the main body 140at a spaced apart position. The vibration generator 150 is sandwichedbetween the spacer 160 and the first end 142 of the main body 140. Apreload bolt 162 is used to secure the spacer 160 to the main body 140.In an exemplary embodiment, the main body 140 includes a threaded bore164 and the preload bolt 162 is threadably coupled to the main body 140in the threaded bore 164. The preload bolt 162 may be secured to themain body 140 by other means in alternative embodiments. The spacer 160may be secured to the main body 140 by alternative means in alternativeembodiments. In an exemplary embodiment, the preload bolt 162 istightened to force the spacer 160 against the vibration generator 150.The vibration generator 150 is likewise pressed against the main body140. The preload bolt 162 may be tightened such that the vibrationgenerator 150 is partially compressed between the spacer 160 and themain body 140.

Vibration caused by the vibration generator 150 is transmitted directlyinto the main body 140 and/or the spacer 160. Optionally, the diecomponent 116 may be positioned within the punch assembly 112 (shown inFIG. 1) such that the spacer 160 abuts against or is otherwise fixed toa component of the punch assembly 112, such as the punch shoe 124, thepunch block 126 and/or the stripper plate 130 (each shown in FIG. 1).Having the spacer 160 fixed relative to the punch assembly 112 allowsthe vibration caused by the vibration generator 150 to be transmittedinto the main body 140. Vibration of the main body 140 is transmittedinto the workpiece 102 during the pressing operation.

In an exemplary embodiment, the piezoelectric actuator 152 includespiezoelectric elements 170, 172. The piezoelectric elements 170, 172 arefabricated from a material that is configured to change shape whenvoltage is applied across such material. For example, the piezoelectricelements 170, 172 may expand and/or contract depending on a polarizationof the voltage applied across the piezoelectric elements 170, 172. In anexemplary embodiment, the piezoelectric elements 170, 172 aremanufactured from a ceramic material and may be referred to hereinafteras ceramic elements 170, 172. The piezoelectric elements 170, 172 may bemanufactured from other materials in alternative embodiments.

The piezoelectric actuator 152 includes electrical elements 174, 176 anda ground element 178. The electrical elements 174, 176 are positioned onthe piezoelectric elements 170, 172, respectively. The ground element178 is positioned between the piezoelectric elements 170, 172.Electrical leads, such as wires, may be electrically connected to theelectrical elements 174, 176 to supply power to the electrical elements174, 176. Any number of piezoelectric elements 170, 172, electricalelements 174, 176 and ground elements 178 may be provided in alternativeembodiments. The piezoelectric elements 170, 172, electrical elements174, 176 and ground elements 178 may have any shape and are not limitedto the disc shape illustrated in FIG. 2.

An insulator 180 is provided between the piezoelectric actuator 152 andthe preload bolt 162. The insulator 180 may also be positioned betweenthe piezoelectric actuator 152 and the spacer 160 and/or the main body140. The insulator 180 provides electrical insulation between thepiezoelectric actuator 152 and the corresponding metal components of thedie component 116.

In an exemplary embodiment, during operation of the piezoelectricactuator 152, when voltage is applied to the electrical elements 174,176, the piezoelectric elements 170, 172 expand or contract depending onthe polarization of the voltage applied to the electrical elements 174,176. The voltage polarization is repeatedly switched at high frequency,causing vibration of the piezoelectric elements 170, 172. Ultrasonicvibration can be achieved. Vibration in other frequency ranges can beachieved in other embodiments. The voltage is switched across theelectrical connections at the electrical elements 174, 176 and theground element 178. The insulator 180 provides insulation between theelectrical connections and the sides of the piezoelectric elements 170,172.

The insulator 180 provides electrical insulation between thepiezoelectric elements 170, 172. The insulator 180 provides electricalinsulation for the piezoelectric elements 170, 172 from the preload bolt162. The insulator 180 provides electrical insulation for thepiezoelectric elements 170, 172 from the masses defined by the spacer160 and the main body 140.

The ultrasonic vibration is transmitted through the main body 140attached to the end of the piezoelectric actuator 152. The spacer 160 isconnected to the main body 140 through the preload bolt 162. Vibrationof the spacer 160 may be transmitted to the main body 140 through thepreload bolt 162. The preload bolt 162 applies a compressive load to thepiezoelectric actuator 152 to hold the components together. In anexemplary embodiment, the mechanical resonance can be controlled byselecting the size of the masses of the main body 140 and spacer 160relative to the piezoelectric elements 170, 172. For example, the sizeand shape of the masses may be selected to achieve a target oscillatingfrequency of the piezoelectric elements 170, 172. Optionally, the shapeof the main body 140 can be designed to concentrate the ultrasonicvibration toward the workpiece engagement surface 146. For example, thesecond end 144 may have a smaller size as compared to the first end 142.The piezoelectric elements 170, 172 may be designed (e.g. sized, shaped,configured) so that the system attains mechanical resonance.Characteristics of the piezoelectric material affect the response toelectric current. A material is selected so that characteristics anddimensions produce mechanical resonance with the masses at certainfrequencies depending on the application.

In an exemplary embodiment, the workpiece engagement surface 146 maydefine a cutting face of the die component 116 and can have any shapedesired to produce the blanking profile. In the illustrated embodiment,the workpiece engagement surface 146 is circular in shape; however othershapes are possible in alternative embodiments. In an exemplaryembodiment, the main body 140 may be a single unitary body between thefirst end 142 and the second end 144. The workpiece engagement surface146 is part of the unitary structure of the main body 140. In analternative embodiment, the workpiece engagement surface 146 may be partof a separate component that is attached to a holder structure of themain body 140. The separate component may be replaceable to change theshape of the workpiece engagement surface 146 and thus change theblanking performed by the die component 116 without changing out othercomponents of the die component 116.

FIG. 4 illustrates a die component 216 formed in accordance with anexemplary embodiment. The die component 216 is similar to the diecomponent 116 (show in FIG. 3) however the die component 216 includes amain body 240 having a holder 242 and a removable punch 244. Theremovable punch 244 defines a workpiece engagement surface 246 of thedie component 216. The main body 240 is a two piece structure.Replacement of the removable punch 244 allows different shaped blanks tobe formed by the die component 216 without removing the other componentsor elements of the die component 216. When the punch 244 becomes worn,the punch 244 may be replaced. The die component 216 includes avibration generator 250, which may be similar to the vibrationgeneration 150 (shown in FIG. 3) and a spacer 260, which may be similarto the spacer 160 (shown in FIG. 3).

FIG. 5 is a flow chart illustrating an exemplary method of operating apress device. The method includes positioning 300 a workpiece between abase assembly and a punch assembly of the press device. The baseassembly may support the workpiece from below. The punch assembly may bedriven toward and away from the base assembly during a pressingoperation. The press device may be part of a progressive die system,where the workpiece is feed into position at the press device on acontinuous feed or reel. The base assembly and the punch assembly haveblanking profiles that are used to form the workpiece during thepressing operation. The workpiece may be punched, stamped, sheared, cut,bent or otherwise have the shape or profile of the workpiece changedduring the pressing operation.

The method includes holding 302 a punch die component at the punchassembly and pressing 304 the punch die component into the workpiece toform the workpiece during a pressing operation of the press device. Thepunch die component is held to engage the workpiece during the pressingoperation. The punch die component may be generally fixed in positionagainst a corresponding punch assembly component, such as a punch shoe,a punch block, a wear plate, a stripper plate, and the like, such thatas the punch assembly is pressed toward the workpiece during a pressstroke of the pressing operation, the punch die component engages andpresses against the workpiece.

The method includes vibrating 306 the punch die component against theworkpiece at a high frequency during the pressing operation. Thevibrating may be caused by a vibration generator part of the punch diecomponent. For example, a piezoelectric actuator may be attached to abody of the punch die component. The piezoelectric actuator has anelectrical element and a piezoelectric element, such as a ceramicelement. Voltage is applied to the electrical element to change shape ofthe piezoelectric element. The voltage may be quickly switched on/off orpositive/negative to cause the piezoelectric element to vibrate. Thevibration is transferred to the body of the punch die component. Thepunch die component may be vibrated at ultrasonic frequencies. The punchdie component is vibrated against and/or through the workpiece duringthe pressing operation.

The die component is vibrated at high frequency to enhance the pressingoperation and forming of the workpiece. The die component may bevibrated many times during each press stroke of the pressing operation.Optionally, the die component is only vibrated during the press strokeand is not vibrated during the return stroke of the pressing operation.Alternatively, the die component may be vibrated for at least a portionof the return stroke. The vibration of the die component may makeshearing or cutting through the workpiece easier. The vibration of thedie component may reduce burrs on the edges of the workpiece. Thevibration of the die component may enhance the edge quality of the edgesof the workpiece. The vibration of the die component may induce lessstress on the die component. The vibration of the die components mayreduce wear on the die component. The vibration of the die component mayallow blanking of thinner material as the die clearances do not need tobe maintained at such precise locations when the die component isvibrated during the pressing operation.

It is to be understood that the above description is intended to beillustrative, and not restrictive. For example, the above-describedembodiments (and/or aspects thereof) may be used in combination witheach other. In addition, many modifications may be made to adapt aparticular situation or material to the teachings of the inventionwithout departing from its scope. Dimensions, types of materials,orientations of the various components, and the number and positions ofthe various components described herein are intended to defineparameters of certain embodiments, and are by no means limiting and aremerely exemplary embodiments. Many other embodiments and modificationswithin the spirit and scope of the claims will be apparent to those ofskill in the art upon reviewing the above description. The scope of theinvention should, therefore, be determined with reference to theappended claims, along with the full scope of equivalents to which suchclaims are entitled. In the appended claims, the terms “including” and“in which” are used as the plain-English equivalents of the respectiveterms “comprising” and “wherein.” Moreover, in the following claims, theterms “first,” “second,” and “third,” etc. are used merely as labels,and are not intended to impose numerical requirements on their objects.Further, the limitations of the following claims are not written inmeans—plus-function format and are not intended to be interpreted basedon 35 U.S.C. §112, sixth paragraph, unless and until such claimlimitations expressly use the phrase “means for” followed by a statementof function void of further structure.

What is claimed is:
 1. A press device comprising: a base assembly havinga base die component configured to form a workpiece; and a punchassembly movable relative to the base assembly during a pressingoperation, the punch assembly having at least one punch die componentpressing the workpiece to form the workpiece, the punch die componentcomprises a main body having a workpiece engagement surface configuredto engage the workpiece formed by the base assembly and the punchassembly, and the punch die component having a vibration generatoroperatively coupled to the main body, the vibration generator causingthe main body of the die component to vibrate at a high frequency duringthe pressing operation.
 2. The press device of claim 1, wherein thevibration generator comprises a piezoelectric actuator.
 3. The pressdevice of claim 1, wherein the vibration generator comprises anelectrical element and a piezoelectric element configured to changeshape when voltage is applied to the electrical element.
 4. The pressdevice of claim 1, wherein the vibration generator causes ultrasonicvibration of the main body.
 5. The press device of claim 1, furthercomprising a spacer coupled to the main body with the vibrationgenerator sandwiched between the spacer and the main body.
 6. The pressdevice of claim 5, further comprising a preload bolt coupled between thespacer and the main body, the preload bolt connecting the spacer to themain body, the preload bolt compressing the vibration generator betweenthe spacer and the main body, vibration of the vibration generator beingtransmitted into the main body.
 7. The press device of claim 5, whereinthe spacer is fixed relative to the punch assembly, vibration of thevibration generator causing the main body to move relative to thespacer.
 8. The press device of claim 1, wherein the workpiece engagementsurface is configured to vibrate against the workpiece during thepressing operation.
 9. The press device of claim 1, wherein the punchassembly is moved along a press stroke and a return stroke during thepressing operation, the vibration generator causing the main body tovibrate against the workpiece multiple times during the press stroke.10. The press device of claim 1, wherein the workpiece engagementsurface directly engages the workpiece.
 11. The press device of claim 1,wherein the main body holds a removable punch, the removable punchdefining the workpiece engagement surface, the removable punch beingconfigured to directly engage the workpiece.
 12. A punch die componentfor a press device, the punch die component comprising: a main bodyextending between a first end and a second end, the main body having aworkpiece engagement surface at the second end configured to engage aworkpiece formed by the press device; a vibration generator coupled tothe first end of the main body, the vibration generator operating tocause the main body to vibrate at a high frequency during a pressingoperation of the press device; and a spacer coupled to the main body ata spaced apart position, the vibration generator being sandwichedbetween the spacer and the first end of the main body.
 13. The punch diecomponent of claim 12, wherein the vibration generator comprises apiezoelectric actuator having an electrical element and a piezoelectricelement configured to change shape when voltage is applied to theelectrical element.
 14. The punch die component of claim 12, wherein thevibration generator causes ultrasonic vibration of the main body. 15.The punch die component of claim 12, further comprising a preload boltcoupled between the spacer and the main body, the preload boltconnecting the spacer to the main body, the preload bolt compressing thevibration generator between the spacer and the main body, vibration ofthe vibration generator being transmitted into the main body.
 16. Thepunch die component of claim 12, wherein the workpiece engagementsurface is configured to vibrate against the workpiece during thepressing operation.
 17. A method of operating a press device, the methodcomprising: positioning a workpiece between a base assembly and a punchassembly of the press device; holding a punch die component at the punchassembly; pressing the punch die component into the workpiece to formthe workpiece during a pressing operation of the press device; andvibrating the punch die component against the workpiece at a highfrequency during the pressing operation.
 18. The method of claim 17,wherein said vibrating the punch die component comprises operating apiezoelectric actuator having an electrical element and a piezoelectricelement by applying a voltage to the electrical element to change shapeof the piezoelectric element.
 19. The method of claim 17, wherein saidvibrating the punch die comprises vibrating the punch die component atultrasonic frequencies.
 20. The method of claim 17, wherein saidvibrating the punch die component comprises vibrating the punch diecomponent through the workpiece.